<form role="search" method="get" class="search-form" action="<?php echo home_url('/'); ?>">
    <div class="input-group">
        <input type="search" class="form-control" placeholder="搜索..." value="<?php echo get_search_query(); ?>" name="s" />
        <button type="submit" class="btn btn-primary">
            <i class="icon iconfont icon-search"></i>
        </button>
    </div>
</form>

<style>
.search-form {
    max-width: 500px;
    margin: 0 auto;
}

.search-form .input-group {
    border-radius: 50px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.search-form input {
    border: none;
    padding: 15px 25px;
    font-size: 16px;
}

.search-form button {
    padding: 0 25px;
    border: none;
    background: #007bff;
    color: white;
}

.search-form button:hover {
    background: #0056b3;
}
</style>
